The present invention relates to a burner construction in which a body portion of a burner is fabricated from a base metal comprising copper or copper alloy. More particularly, the present invention relates to such a burner construction in which a protective coating, comprising nickel or a nickel based alloy, is applied to the base metal.
In many industrial activities burners are used to heat materials to their melting point in order to process such materials as melts. For instance, Burners find wide application in the glass, aluminum and steel making industries. Typically, industrial burners are fabricated from stainless steel and are designed to burn a liquid or gaseous fuel in air, oxygen enriched air or purified oxygen. The problem with using stainless steel, is that at high temperatures, the body of the burner from which the flame emanates, can oxidize and melt. This problem is particularly acute when combustion temperatures are increased by provision of oxygen or oxygen enrichment.
In burners fabricated from stainless steel, oxidation is most severe at extreme temperatures that approach the melting point of the steel. Although the entire surface of the burner that is exposed to the furnace atmosphere can be oxidized, oxidation is particularly pronounced at the tip of the burner. The reason for this is that a hot spot develops at the tip of the burner due to the low thermal conductivity of stainless steel. The hot spot can also cause melting. In order to eliminate the potential for melting, higher conductivity materials have been used for burners such as copper and copper alloys. Copper or alloys of copper as a burner material can also be problematical in certain applications involving furnace environments containing sulfur. In such environments copper will not only oxidize but experience sulfidation.
As will be discussed, the present invention provides a burner construction that is resistant to oxidation and sulfidation.